Study on Microstructure and Mechanical Properties of Epoxy Resin/Carbon Black Composites Prepared by in Situ Polymerization

2011 ◽  
Vol 109 ◽  
pp. 156-160 ◽  
Author(s):  
Xue Feng Lu ◽  
Pei Qing La ◽  
Xin Guo ◽  
Yu Peng Wei

Microstructure and mechanical properties of epoxy resin/carbon black composites synthesized by in situ condensation polymerization of monomers in the presence of carbon black particles were investigated. SEM observation showed that carbon black particles were well dispersed in the epoxy resin matrix. The composite with 1 wt. % carbon black had the electrical resistivity of approximately 108.7 Ω•cm. The composites exhibited an a percolation threshold at carbon black content about 4 wt.%, indicating the existence of a path of percolation by connecting carbon black particles. Bending strength dramatically increased to a maximum value of 133.4MPa and then slowly decreased with content of carbon black increasing. Shore hardness increased gradually with content of carbon black and came to 23.3HD at carbon black 10 wt.%.

2006 ◽  
Vol 510-511 ◽  
pp. 758-761 ◽  
Author(s):  
Hyeong Ho Jin ◽  
Sang Ho Min ◽  
Kyu Hong Hwang ◽  
Ik Min Park ◽  
Hong Chae Park ◽  
...  

Biodegradable β-tricalcium phosphate (β-TCP)/poly (lactide-co-glycolide) (PLGA) composites were synthesized by in situ polymerization with microwave energy. The influence of the β-TCP content in β-TCP/PLGA composites on the molecular weight, crystallinity, microstructure, and mechanical properties was investigated. As the molecular weight of composites decreased, the β-TCP content increased up to 10 wt%, while further raising of the β-TCP content above 10%, the molecular weight increased with increasing β-TCP content. This behavior may be ascribed to the superheating effect or nonthermal effect induced by microwave energy. It was found that the bending strength and Young’s modulus of the β-TCP/PLGA composites were proportional to the molecular weight of PLGA. The bending strength of the β-TCP/PLGA composites ranged from 18 to 38 MPa, while Young’s modulus was in the range from 2 to 6 GPa.


2011 ◽  
Vol 415-417 ◽  
pp. 358-361
Author(s):  
Xue Feng Lu ◽  
Pei Qing La ◽  
Xin Guo ◽  
Yu Peng Wei

Synthesis and properties of epoxy resin/graphite composites via in situ condensation polymerization of monomers in the presence of graphite particles were investigated. The results showed graphite particles were well dispersed in the epoxy resin matrix. Shore hardness and bending strength varied with the amount of graphite, and they were all improved greatly by an optimal content of 17.44 % (mass fraction). The bending strength was 22.4MPa and Shore hardness was 9.8 HD. A plastic deformation can be seen in the composite with the range of strain 0.6-0.8%. The fitted yield strength is about 20MPa.


Crystals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 422
Author(s):  
Kuai Zhang ◽  
Yungang Li ◽  
Hongyan Yan ◽  
Chuang Wang ◽  
Hui Li ◽  
...  

An Fe/FeAl2O4 composite was prepared with Fe-Fe2O3-Al2O3 powder by a hot press sintering method. The mass ratio was 6:1:2, sintering pressure was 30 MPa, and holding time was 120 min. The raw materials for the powder particles were respectively 1 µm (Fe), 0.5 µm (Fe2O3), and 1 µm (Al2O3) in diameter. The effect of sintering temperature on the microstructure and mechanical properties of Fe/FeAl2O4 composite was studied. The results showed that Fe/FeAl2O4 composite was formed by in situ reaction at 1300 °C–1500 °C. With the increased sintering temperature, the microstructure and mechanical properties of the Fe/FeAl2O4 composite showed a change law that initially became better and then became worse. The best microstructure and optimal mechanical properties were obtained at 1400 °C. At this temperature, the grain size of Fe and FeAl2O4 phases in Fe/FeAl2O4 composite was uniform, the relative density was 96.7%, and the Vickers hardness and bending strength were 1.88 GPa and 280.0 MPa, respectively. The wettability between Fe and FeAl2O4 was enhanced with increased sintering temperature. And then the densification process was accelerated. Finally, the microstructure and mechanical properties of the Fe/FeAl2O4 composite were improved.


2013 ◽  
Vol 785-786 ◽  
pp. 533-536 ◽  
Author(s):  
Shi Bao Li ◽  
Yi Min Zhao ◽  
Jian Feng Zhang ◽  
Cheng Xie ◽  
Dong Mei Li ◽  
...  

A novel PMMA-ZrO2 composite (PZC) was prepared by resin infiltrated to ceramic method. The composite mechanical properties were evaluated and correlated to its microstructure. Partially sintered zirconia ceramics (PSZC) were made by isostatic pressing and partially sintering. Subsequently, the PZC was prepared by vacuum infiltrating prepolymerized MMA into PSZC, followed by in-situ polymerization. When PSZC-70% was used as the matrix, the bending strength, elastic modulus, and fracture toughness of the prepared composite i.e PZC-70% were 202.56±12.09 MPa, 58.71±3.98 GPa, and 4.60±0.26 MPa·m1/2, corresponding to 25.69%, 23.31%, and 169.01% improvement, respectively, in comparison with the control matrix. Among them, the fracture toughness improvement was the most prominent. According to SEM images of the fracture surfaces, each pore of zirconia skeleton was filled by organic resin contributing to the bending strength improvement. These weak interfaces between zirconia skeleton and organic resin absorbed energy and terminated the growth of microcracks which might be responsible for significant improvement in fracture toughness. This PZC material is anticipated to be a new member of the dental CAD/CAM family.


2007 ◽  
Vol 336-338 ◽  
pp. 1164-1167
Author(s):  
Yun Long Yue ◽  
Hai Tao Wu ◽  
Wei Bing Wu ◽  
Hai Yan Yin

In this paper Ti2AlC/TiAl composites were in-situ fabricated by spark plasma sintering (SPS) and then the effects of rapid heat-treatment on microstructure and mechanical properties of Ti2AlC/TiAl composites were investigated. After rapid heat-treatment the microstructure of TiAl matrix was significantly transformed from the near γ microstructure to duplex microstructure. Ti2AlC particles effectively refined the γ phase grains and the α2/γ lamellar colony microstructure. For the Ti2AlC/TiAl composite after rapid heat-treatment at 1200°C, the bending strength and fracture toughness reached 956.8MPa and 22.8MPa·m1/2, respectively.


Polymers ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2058 ◽  
Author(s):  
George Soupionis ◽  
Pantelitsa Georgiou ◽  
Loukas Zoumpoulakis

The present paper deals with the use of polymeric matrix composite materials reinforced with carbon fiber as concrete shear reinforcement materials. Accordingly, cement specimens were manufactured and coated with various types of carbon fabrics and epoxy resin in liquid and solid form (paste). Additionally, composite materials of epoxy resin matrix reinforced with carbon fiber fabrics were manufactured. In all the specimens, the mechanical properties were estimated; the cement samples coated with composite materials of epoxy resin matrix reinforced with carbon fiber fabrics were tested for compressive strength, while the other specimens were tested for shear and bending strength. The specimens were subjected to artificial aging through heat treatment for 8, 12 and 16 days. During the process of artificial aging, the temperature in the chamber reached the range of 65–75 °C. These composite materials exhibited high mechanical properties combined with adaptability. Both an external deterioration of the materials as well as a reduction in mechanical properties during their artificial aging heat treatment were observed. This was shown in the specimens that were not subjected to artificial aging, with an applied compression strength of 74 MPa, and after the artificial aging, there was a decrease of ~7%, with the compression strength being reduced to 68 MPa.


2014 ◽  
Vol 910 ◽  
pp. 70-73
Author(s):  
Tao Wang ◽  
Jun Wang ◽  
Bin Zhang

P(BA-St), a good modifier for epoxy resin, was prepared by BA and St in situ polymerization. The modified resin system was based on diglycidyl ether of bisphenol and methyl tetrahydrophthalic anhydride, tris (dimethylaminomethyl) phenol. The influence of the copolymer on mechanical properties and thermal performance of the systems was studied. When 15 wt% of the BA/St with a weight ratio composition of 7.5/7.5 was added to epoxy, high performance modified epoxy resin was obtained.


Coatings ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 666
Author(s):  
Chong Li ◽  
Haoyu Wang ◽  
Xiaolei Zhao ◽  
Yudong Fu ◽  
Xiaodong He ◽  
...  

As an efficient reinforcing material in resin matric composites, the application of basalt fibers (BFs) in composites is limited by the poor interfacial adhesion between BFs and the resin matrix. In this study, to obtain the basalt fibers/epoxy resin composites with enhanced mechanical properties, the modification solution containing different concentrations of Lanthanum ions (La3+) was synthesized to modify the BFs surfaces to enhance the poor interfacial adhesion between BFs and the matrix. The morphology, the chemical structure and the chemical composition of the modified BFs surface were observed and detected by scanning electron microscopy, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy, respectively. The results show that, after BFs were soaked in the modification solution, the more active groups (C=O, –OH, C–O, etc.) were introduced to the BFs surfaces and effectively enhanced the bond strength between BFs and the resin matrix. The obtained mechanical performances of prepared basalt fibers/epoxy resin composites showed that the tensile strength, bending strength and interlaminar shear strength (ILSS) were improved with the modified BFs, and reached to 458.7, 556.7 and 16.77 Mpa with the 0.5 wt.% La. Finally, the enhancement mechanism of the modification solution containing La element is analyzed.


Crystals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 204
Author(s):  
Kuai Zhang ◽  
Yungang Li ◽  
Chuang Wang ◽  
Hongyan Yan ◽  
Hui Li ◽  
...  

The Fe/FeAl2O4 cermet was prepared with Fe-Fe2O3-Al2O3 powder by a hot press sintering method at 1400 °C. The raw materials for the powder particles were respectively 2 µm (Fe), 0.5 µm (Fe2O3), and 0.5 µm (Al2O3) in diameter, the sintering pressure was 30 MPa, and the holding time was 120 min. The effects of different Fe mass ratios on the microstructure and mechanical properties of Fe/FeAl2O4 cermet were studied. The results showed that a new ceramic phase FeAl2O4 could be formed by an in situ reaction during the hot press sintering. When the Fe mass ratio was increased, the microstructure and mechanical properties of the Fe/FeAl2O4 cermet showed a change law that initially became better and then became worse. The best microstructure and mechanical properties were obtained in the S2 sample, where the mass ratio of Fe-Fe2O3-Al2O3 was 6:1:2. In this Fe mass ratio, the relative density was about 94%, and the Vickers hardness and bending strength were 1.21 GPa and 210.0 MPa, respectively. The reaction mechanism of Fe in the preparation process was the in situ synthesis reaction of FeAl2O4 and the diffusion reaction of Fe to FeAl2O4 grains. The increase of the Fe mass ratio improved the wettability of Fe and FeAl2O4, which increased the diffusion rate of Fe to FeAl2O4 grains, which increased the influence on the structure of FeAl2O4.


2014 ◽  
Vol 633 ◽  
pp. 49-52
Author(s):  
Yun Long Ai ◽  
Kai Wu ◽  
Xiang Hua Xie ◽  
Bing Liang Liang ◽  
Wen He ◽  
...  

Nb2O5-7.5La2O3-Al2O3 composite ceramics were prepared by microwave sintering. The influence of Nb2O5 and La2O3 proportion on the microstructure and mechanical properties of Al2O3 ceramics was investigated. The results show that when the Nb2O5 content was lower than La2O3, the columnar LaAl11O18 grains were generated by the reaction of La2O3 with Al2O3. When the Nb2O5 content was higher than La2O3, the surplus Nb2O5 induced the formation of columnar Al2O3 grains. The growth of columnar Al2O3 grains were promoted synergistically by LaNbO4 formed in-situ and Nb2O5. The 5Nb2O5-7.5La2O3-Al2O3 composite ceramic exhibited excellent comprehensive properties: ρr=99.3% (relative density), HV=11.2GPa (microhardness), KIC= 6.4MPa·m1/2 (fracture toughness), σ=304.3MPa (bending strength).


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